Electromagnetic relay

Abstract

The electromagnetic relay has a pair of normally closed and normally open fixed terminals which are disposed opposing each other. At least two normally closed fixed contacts are mounted on the normally closed fixed terminal, and at least two normally open fixed contacts are mounted on the normally open fixed terminal. The normally closed and normally open fixed terminals are commonly used by a plurality of relay units. Therefore, the relay can be small enough to be installed on a small area, and allows high-density electric circuits to be provided on circuit boards.

What is claimed is: 
     
       1. An electromagnetic relay comprising: at least two electromagnetic devices, each having a coil device;   a pair of normally closed and normally open fixed terminals which are disposed opposing each other, said pair of fixed terminals being located on one side of said coil device;   at least two normally closed fixed contacts mounted on said normally closed fixed terminal;   at least two normally open fixed contacts mounted on said normally open fixed terminal, each of said normally open fixed contacts opposing each of said normally closed fixed contacts; and   at least two movable contacts, each of which is reciprocated between said normally closed and open fixed contacts by activating and deactivating said electromagnetic device.   
     
     
       2. An electromagnetic relay according to claim 1, in which each device further comprises a pair of terminal bases for supporting said normally closed and normally open fixed terminals. 
     
     
       3. An electromagnetic relay according to claim 2, wherein each of said terminal bases has two grooves, into one of which said normally closed fixed terminal is fitted, and into the other of which said normally open fixed terminal is fitted. 
     
     
       4. An electromagnetic relay according to claim 2, wherein said normally closed and normally open fixed terminals have flat portions whose tips are bent downwardly to form protrusions, and said terminal bases have recesses into which said protrusions are fitted. 
     
     
       5. An electromagnetic relay according to claim 1, further comprising a terminal base for supporting around the central parts of said normally closed and normally open fixed terminals. 
     
     
       6. An electromagnetic device according to claim 1, wherein said electromagnet devices have two common flanges at both ends thereof which are extended in the width direction, one of said common flange has a first recess formed on the upper portion thereof and the other has a second recess formed on the lower portion thereof opposing said first recess, and one of said coil devices is slided onto said flanges through said recesses. 
     
     
       7. An electromagnetic relay comprising: a normally closed fixed terminal having two normally closed contacts thereon;   a normally open fixed terminal having two normally open contacts, each of said normally open contacts opposing each of said normally closed contacts;   a pair of common terminals each of which has a pair of common contacts, one of said common terminals being disposed near one side of said normally open and said normally closed fixed terminals and the other of said terminals being disposed near the other side of said normally open and said normally closed fixed terminals;   first and second movable contact members each of which has two movable contacts, one of said movable contacts of each of said movable contact members being disposed between said normally closed and open contacts, and the other of said movable contacts of each of said movable contact members being disposed between said common contacts;   a first electromagnetic device for moving said first movable contact member to changeover an electric circuit; and   a second electromagnetic device for moving said second movable contact member to changeover an electric circuit.   
     
     
       8. An electromagnetic relay according to claim 7 further comprising first and second movable iron members, said first movable iron member is rotatably mounted on said first electromagnetic device for moving said first movable contact member, said second movable iron member is rotatably mounted on said second electromagnet device for moving said second movable contact member. 
     
     
       9. An electromagnetic relay according to claim 1, wherein each device further comprises a terminal block on which each pair of normally closed and normally open fixed terminals is mounted, which terminal block is mounted within the relay substantially contiguously with the terminal block of the other device within said relay.